The present invention relates to a display device, for example, to a technology applicable to a lighting inspection circuit to illuminate and inspect a display panel.
In an active matrix type display device, in an area near a cross of each scanning line (hereinafter called a gate line) and each video signal line (called a source line or also a drain line, and hereinafter called a source line), a thin-film transistor (TFT) turned on by a scanning signal from the gate line and a pixel electrode supplied with a picture signal from the source line via the above thin-film transistor are formed to form a pixel. The area to form a plurality of pixels is a display area, around which a peripheral area (frame area) is present. In this peripheral area, semiconductor chips forming a scanning line driving circuit, wiring (terminal wiring) to connect the gate lines and source lines on the display area to the semiconductor chip, etc. are provided.
In recent years, with higher definition of display images to improve recognition of information, the number of pixels is increasing and the number of source lines and gate lines is increasing. With these increases, in addition to the number of inputs and outputs of a semiconductor ship device, the number of terminal lines is also increasing. Therefore, a technology to form a semiconductor chip and many terminal lines on a peripheral area having a limited size is desired.
For example, Japanese Unexamined Patent Application Publication No. 2011-164361 (Patent Document 1) discusses a way to address that request. Patent Document 1 discusses a (small line pitch) technology to make small spaces between terminal lines by bending each terminal line adjacent to a terminal (terminal contact hole) formed on each terminal line. In addition, a technology to form an inspection circuit (hereinafter called a lighting inspection circuit) that carries out a pseudo dynamic lighting inspection in that line pitch, which is a failure detection way for liquid crystal display devices (liquid crystal display panels) is also discussed. After the search of the related technologies on the basis of the result invented by the present inventors, Japanese Unexamined Patent Application Publication No. 2010-102237 and Japanese Unexamined Patent Application Publication No. 2009-237280 have been found.